Debt - Aggregate Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Summary of aggregate maturities of debt obligations
2022	$ 12,868
2023	9,239
2024	4,322
2025	1,397
2026	8,306
Total debt	36,132	$ 85,797
bp Loan
Summary of aggregate maturities of debt obligations
Total debt		50,000
NG Advantage debt
Summary of aggregate maturities of debt obligations
2022	2,991
2023	8,977
2024	4,161
2025	1,397
2026	8,306
Total debt	25,832	29,535
Term Loan Facility
Summary of aggregate maturities of debt obligations
2022	9,500
Total debt	9,500	5,100
Other debt
Summary of aggregate maturities of debt obligations
2022	377
2023	262
2024	161
Total debt	$ 800	$ 1,162

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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